The primary objective of this study is to evaluate the pre-operative (approximately -90 to -1 day before surgery) to minimum one year (approximately 304 to 668 days) postoperative functional performance improvement for the Attune™ primary, cemented TKA system as measured by the activities of daily living (ADL)subscore of the Knee Osteoarthritis Outcomes Score (KOOS)questionnaire (KOOS-ADL sub-score). This will be carried out for all four implant configurations: cruciate retaining fixed bearing (Attune™ CR FB), cruciate retaining rotating platform (Attune™ CR RP), posterior stabilized fixed bearing (Attune™ PS FB), and posterior stabilized rotating platform (Attune™ PS RP).